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I'm thinking I need an app that immediately encrypts the flash should it ever detect its been placed in a "Faraday bag". I've actually tried to isolate a phone

I'm thinking I need an app that immediately encrypts the flash should it ever detect its been placed in a "Faraday bag". I've actually tried to isolate a phone from the network for testing. Its much more difficult that it seems like it should be. I'm wondering if such a thing works or if this more of a gimmick. The only reliable way I've found of making sure my iphone is truly off the air is to take it to San Fran(1)... (1) I'll be here all week. Try the veal.

morganpyne 16y ago
You could take a lesson from the Mozilla Foundation about isolating phones in Faraday Cages: http://oduinn.com/blog/2010/02/11/unveiling-mozillas-faraday-cage/ http://oduinn.com/blog/2010/02/11/unveiling-mozillas-faraday... Or you could stick it in a microwave. (I've used this to test if my home 'repaired' microwave is leaking radiation. Stick your phone in it and close the door. Call it. If it rings, chuck your microwave out :-) If it doesn't, well, I wouldn't stake my life on it not leaking and I'd still get it tested professionally. Only problem with this microwave trick is that it's hard to push the buttons once the door is closed! You can use it to test your microwave, but not your phone unless your app doesn't need any interaction. Also, an app that encrypts on loss of signal would be of limited use where I live in NZ. The Vodafone network drops in and out so often you'd flatten the battery on the phone real fast with all that encryption action.
- noonespecial 16y ago
  Yeah, I was thinking about that. It couldn't just encrypt on "no signal". On a rooted Pre I have, I'm able to get lots of radio stuff even when the phone is saying "no signal" and I can't make calls. The noise floor is a pretty good place to start. I'm thinking just monitoring the noise and watching for very sudden changes. If you suddenly change rapidly to very quiet, you might be in a faraday bag. Hmm. It actually can only report the SNR. I'll have to look into how it comes up with this number. Thanks for the microwave tip. Might be handy.
- jemfinch 16y ago
  If your phone doesn't ring and you're not feeling warmth when the microwave runs, you're fine. Microwaves don't do much more than excite water molecules. Those excited molecules would manifest as a simple perception of increased heat if there's somewhere your microwave is leaking. If you're not feeling that, you're safe.
- shasta 16y ago
  I use my microwave to get off of the phone. I put it on mute before I stick it in so that they don't hear the door closing.

morganpyne 16y ago

You could take a lesson from the Mozilla Foundation about isolating phones in Faraday Cages: http://oduinn.com/blog/2010/02/11/unveiling-mozillas-faraday-cage/ http://oduinn.com/blog/2010/02/11/unveiling-mozillas-faraday... Or you could stick it in a microwave. (I've used this to test if my home 'repaired' microwave is leaking radiation. Stick your phone in it and close the door. Call it. If it rings, chuck your microwave out :-) If it doesn't, well, I wouldn't stake my life on it not leaking and I'd still get it tested professionally. Only problem with this microwave trick is that it's hard to push the buttons once the door is closed! You can use it to test your microwave, but not your phone unless your app doesn't need any interaction. Also, an app that encrypts on loss of signal would be of limited use where I live in NZ. The Vodafone network drops in and out so often you'd flatten the battery on the phone real fast with all that encryption action.

noonespecial 16y ago
Yeah, I was thinking about that. It couldn't just encrypt on "no signal". On a rooted Pre I have, I'm able to get lots of radio stuff even when the phone is saying "no signal" and I can't make calls. The noise floor is a pretty good place to start. I'm thinking just monitoring the noise and watching for very sudden changes. If you suddenly change rapidly to very quiet, you might be in a faraday bag. Hmm. It actually can only report the SNR. I'll have to look into how it comes up with this number. Thanks for the microwave tip. Might be handy.
jemfinch 16y ago
If your phone doesn't ring and you're not feeling warmth when the microwave runs, you're fine. Microwaves don't do much more than excite water molecules. Those excited molecules would manifest as a simple perception of increased heat if there's somewhere your microwave is leaking. If you're not feeling that, you're safe.
shasta 16y ago
I use my microwave to get off of the phone. I put it on mute before I stick it in so that they don't hear the door closing.